This invention relates to brush attachments for power tools including an attachment designed to convert rotary motion provided by a power tool to reciprocating motion.
Various brush designs intended for cleaning purposes are known and have been used for a considerable length of time. These include brushes intended for use on various power tools. For example, it is known to use large rotating brushes on floor polishing equipment. Often the bristles on these brushes are soft and flexible so as not to damage the surface which is being cleaned and to provide a shiny finish to the surface. Rotating brushes are also known for use in cleaning attachments such as those typically used in conjunction with vacuum cleaners. These brushes are used to pick up dirt and lint from the surface being cleaned, which is often a carpet or rug.
Very stiff wire brushes are also known for use in certain cleaning and abrading operations. For example, wire brushes are known for removing rust from metal surfaces or for removing old paint. Generally speaking, wire brushes of this type are only used where the strong, metal bristles will not damage the surface that is being cleaned.
The use of machines for sandblasting is also well known for cleaning certain surfaces such as brick and stone work as well as metal surfaces. Generally speaking, these machines are intended for large cleaning jobs as they tend to be relatively expensive and generally require the use of a large air compressor. Standard sandblasting techniques can create considerable dust and other debris and therefore such cleaning methods are normally used outside in an environment where the dust and debris can be tolerated. However, sandblasting does have the advantage of providing a relatively quick method for cleaning surfaces that are very difficult to clean by other methods, such as by brushing and washing.
Early U.S. Pat. No. 1,007,888 dated Nov. 7, 1911 and issued to P. W. Parker describes a special brush device designed for use in association with a vacuum cleaner. The brush is rotated by its own electric motor mounted in a specially shaped housing. On an extension of this housing is mounted an elongate sleeve having a cam mounted at one end. This cam co-acts with a further cam which extends around a shaft that is connected to the shaft coming from the motor. A coiled spring is connected to the latter cam. At the forward end of the first mentioned shaft is an annular brush which can be made with stiff wire or fiber. This brush is mounted in the intake end of the vacuum tube. The device can be arranged to impart both a reciprocatory and a rotary movement to the brush by means of engagement between the cams. This known device is said to be suitable for cleaning stone, cement and similar surfaces where a slight abrasive action is desired. A difficulty with this known device is that it is only designed for use in conjunction with a special vacuum cleaner attachment.
A more recent patent illustrating a mechanism for reciprocating a cleaning brush is U.S. Pat. No. 2,671,914 issued Mar. 16, 1954 to R. V. Rucker. This specification teaches a mechanism for converting rotary motion to a reciprocal lateral motion. It requires the use of a dedicated electric motor mounted in a hollow housing that is connected to a handle. The motor turns a bevelled pinion gear which rotates a drive gear having a gear segment affixed thereto. This gear segment engages a rectangular rack causing it first to reciprocate in one direction when its upper teeth are engaged and reciprocate in the opposite direction when its lower teeth are engaged. This reciprocating rack has a brush affixed thereto. Means are also provided for pumping liquid from a reservoir to the brush.
An object of the present invention is to provide an easy to use brush attachment useful for cleaning, particularly the cleaning of surfaces where a sandblasting technique would normally be called for. Another object of the present invention is to provide a brush attachment that can readily be mounted on existing, widely used power tools, such as a power drill, thus reducing the cost of the device substantially. The attachment is able to selectively either rotate the brush about an axis parallel to the bristles or reciprocate the brush in the longitudinal direction of the bristles.
It is a further object of the invention to provide a unique brush construction that is particularly suited for cleaning in a manner that might be considered similar to sandblasting. This unique brush attachment employs tough, flexible bristles which are capable of restoring themselves substantially to their original shape after repeated bending. The bristles of the brush can vary in length from long, centrally located bristles, to shorter bristles located at two opposite sides of the brush.
In the preferred embodiment of the brush, there is a brush body which is generally rectangular with a central longitudinal axis and the long bristles extend along this longitudinal axis. In one preferred embodiment of the brush, the bristles are made of a stiff, wavy polypropylene or nylon material.